At present, touch panel, as the latest computer input device, is the most simple, convenient and natural mode of human-computer interaction. With the increasing use of computers, touch panel has been more and more widely used for its advantages such as easy-to-use, firmness, durability, fast response and space-saving and the like.
Particularly, OGS touch panel, which is light and thin and has high light transmittance and excellent display effect, is a medium- and high-end product in accordance with the development tendency of touch panels. However, the pass yield thereof is difficult to control for its complicate fabrication process. Particularly, the singleton defect rate reaches about 5%, while the defect rate after bonding even reaches up to 10% to 20%. A large amount of scrapped touch panel products resulted by such high defect rates have constructed a main part of electrical and electronic wastes. OGS touch panel contains high-strength glass, indium tin oxide, and other metals and polymer materials, which are seldom recycled effectively currently, thus causing not only resources waste but also environment pollution. Especially, the rare metal of indium contained in the indium tin oxide, which has a very small content and distributes discretely in the earth crust, and is high in price, plays an irreplaceable role in the display field and other electronic information industry, therefore it is very valuable to recycle the metal indium.
CN 102629173A discloses a method for recycling an ITO conductive film from a capacitive touch screen, comprising the following steps: a. freezing: freezing the defective capacitive touch screen in a freezer at −90 to −70° C. for 25 to 35 min; and b. disassembling: disassembling the frozen capacitive touch screen and recycling the conductive film bonded on the composite glass screen. During the disassembling and recycling of the capacitive touch screen, the adhesion of the double-sided adhesive between the composite glass screen and the ITO conductive film is weakened after freezing, so the ITO conductive film can be effectively disassembled down from the composite glass screen and then be recycled, thus saving resources.
The above recycling method is suitable for the capacitive touch screen having a GF structure. However, as for OGS touch screen, the ITO pattern layer used as a touch electrode is directly formed on the glass and there is no separate ITO conductive film, therefore such method cannot be used for the disassembling and recycling of the OGS touch screen.
Thus, how to recycle indium from various kinds of panels is a problem urgently to be solved in the art.